%0 Journal Article
%T The diketopiperazine-fused tetrahydro-¦Â-carboline scaffold as a model peptidomimetic with an unusual ¦Á-turn secondary structure
%A Francesco Airaghi
%A Andrea Fiorati
%A Giordano Lesma
%A Manuele Musolino
%J Beilstein Journal of Organic Chemistry
%D 2013
%I 
%R 10.3762/bjoc.9.17
%X Aiming at restricting the conformational freedom of tryptophan-containing peptide ligands, we designed a THBC (tetrahydro-¦Â-carboline)-DKP (diketopiperazine)-based peptidomimetic scaffold capable of arranging in an unusual ¦Á-turn conformation. The synthesis is based on a diastereoselective Pictet¨CSpengler condensation to give the THBC core, followed by an intramolecular lactamization to complete the tetracyclic THBC-DKP fused ring system. The presence of conformers bearing the intramolecular thirteen-membered hydrogen bond that characterizes the ¦Á-turn structure is confirmed by 1H NMR conformational studies. To the best of our knowledge, this scaffold represents one of the rare examples of a designed constrained ¦Á-turn mimic.
%K ¦Á-turn
%K conformational analysis
%K diketopiperazine
%K peptidomimetics
%K tetrahydro-¦Â-carboline
%U http://dx.doi.org/10.3762/bjoc.9.17